Trifluoromethylbenzophenone o-acyl-oximes useful as crop yield increasers for plants

ABSTRACT

1. A COMPOUND OF THE FORMULA   R-(PHENYLENE)-C(=N-OOC-R1)-(PHENYLENE)-CF3   R IS H, METHYL, TRIFLUOROMETHYL OR METHOXY; AND WHEREIN R1 IS PHENYL, ALKYL OR HALOALKYL OF UP TO 11 CARBON ATOMS.

United States Patent O 3,849,494 TRIFLUOROMETHYLBENZOPHENONE O-ACYL-OXIMES USEFUL AS CROP YIELD INCREASERS FOR PLANTS William JosephMiddleton, Chadds Ford, Pa., assignor to E. I. du Pont de Nemours andCompany, Wilmington, Del. No Drawing. Filed Jan. 18, 1973, Ser. No.324,878 Int. Cl. C07c 131/00 U.S. Cl. 260566 AE 8 Claims ABSTRACT OF THEDISCLOSURE Certain trifluoromethylbenzophenone O-acyloximes are cropyield increasers for plants. Exemplary is 4-trifluoromethylbenzophenoneO-acetyloxime.

BACKGROUND OF THE INVENTION Field of the Invention This inventionrelates to trifluoromethylbenzophenone O-acyloximes and their use ascrop yield lncreasers for plants.

Prior Art The unacylated 2- and 3-trifluorornethylbenzophenone oximesare known [Lichtenberger & Weiss, Bull. Soc. Chim., France, 587 (1962);Chem. Abs., 57, 2126 (1963)]. 4-trifluoromethylbenzophenone oxime isdisclosed in words in Chem. Abs. Cumulative Index for 1962-66, AMN-BEvolume, p. 31938, but this index disclosure is erroneous. It concernsthe above Lichtenberger & Weiss reference, which does not mention4-trifluoromethylbenzophenone or its oxime.4-trifluoromethylbenzophenone, however, is known [Rossi & Butta, Chem.Abs., 56, 12895 (1962)]. 4-Methoxy-4-trifluoromethylbenzophenone oximeis known [Buu-Hoi et al., Rec. Trav. Chim., 85, 367 (1966)].Benzophenone O acetyloxime is :known [Exner, Chem. Listy, 48, 1634(1954)]. The oximes per se are generally less stable than the acylatedderivatives and are not known to exhibit crop yield increasing effectson plants.

SUMMARY OF THE INVENTION The novel compounds includetrifinoromethylbenzophenone O-acyloximes, including synand anti-isomersand mixtures thereof, of the formula o-lLm wherein R is hydrogen,methyl, trifluoromethyl or methoxy, R is phenyl, alkyl of 1 to 11carbons, haloalkyl of 1 to 11 carbons, phenylamino, or alkylamino of 1to 3 carbons, and the R and CF groups each can be in the ortho, meta orpara positions. Preferred are those compounds where R=H and the CF groupis in the para position, i.e., the acyloximes of4-trifluorornethylbenzophenone.

The oxime precursors of the compounds of formula I are obtainedconventionally by reaction of the appropriatetrifluoromethylbenzophenone with hydroxylamine hydrochloride in asuitable solvent and the presence of a base,

The trifiuoromethylbenzophenone O-acyloximes of formula I in which R isalkyl or phenyl are obtained conventionally by reaction of thecorresponding oxime with the appropriate carboxylic acid chloride oranhydride in a suitable solvent. The O-acyloximes in which R isalkylamino or phenylamino are obtained by reaction of the correspondingoxime with the appropriate alkyl isocyanate or phenyl isocyanate in asuitable ether solvent.

3,849,494 Patented Nov. 19, 1974 Representativetrifluoromethylbenzophenone O-acyloximes of the invention correspond tocompounds of formula I having the R and R groups given in the followingtable. These compounds include the synand anti-isomers and mixturesthereof, and it is understood that the R and CF groups each may be inthe ortho, meta or para position.

The trifiuoromethylbenzophenone-O-acyloximes of the invention are usefulas crop yield increasers for plants. For example, they enhance theproduction capacity of soybeans as evidenced by increased amounts ofpods and seeds obtained from plants which have been treated with aqueoussuspensions of such O-acyloximes.

SPECIFIC EMBODIMENTS OF THE INVENTION The following examples illustratethe preparation and physical properties of representative noveltrifiuoromethylbenzophenone O-acyloximes and their use as senescenceinhibitors for plants. In these examples temperatures are given indegrees centigrade except where otherwise indicated.

Example 1.4-Trifluoromethylbenzophenone Oxime NOH To a mixture of 50 g.(0.20 mole) of 4-trifluoromethylbenzophenone, 30 g. of hydroxylaminehydrochloride, ml. of ethanol and 45 ml. of water was added, withstirring and cooling, 55 g. of powdered sodium hydroxide. The mixturewas refluxed 5 minutes, cooled and poured into a solution of 150 ml. ofconcentrated hydrochloric acid in 1 liter of water. The product wasfiltered off, Washed with water and vacuum dried over P 0 to give 52.8g. (99.5%) of 4-trifluorornethylbenzophenone oxime as a white powderysolid: mp. -155 C.; F NMR [(CD CO] 6 62.5 p.p.m. (s) overlappingmultiplet at 0.7 Hz. higher field.

Example 2.--4-Trifluoromethylbenzophenone O-Acetyl- To a solution of2.65 g. (0.01 mole) of 4-trifluoromethylbenzophenone oxime in 10 ml. ofdiethyl ether was added 1.0 g. (0.013 mole) of acetyl chloride. Thesolution was stirred 1 hour at room temperature, then added to 20 g. ofice. The ether was evaporated after the ice had melted. The solid whichformed was filtered off, washed with water and dried over P The crudeproduct was recrystallized from n-heptane to give 1.7 g. (55%) of4trifluoromethylbenzophenone O-ocetyloxime as white crystals: m.p.,165170 C. (with some decomposition); IR (KBr) 5.61/4 c=o), 6.17,. C=N);H NMR (CH Cl 6 7.47 p.p.m. (m, 9H), 6 2.02 p.p.m. (s, 3H), 61.57 p.p.m.(impurity, 0.5H).

Analysis.Calcd. for C H NO F C, 62.54; H, 3.94; N, 4.56; F, 18.76 (M.W.,307.28). Found: C, 62.15; H, 3.69; N, 4.60.

In a separate experiment, 170 g. (2.17 mole) of acetyl chloride wasadded dropwise to a solution of 450 g. (1.70 mole) of4-trifluoromethylbenzophenone oxime in 1.5 liter of ether. The mixturewas stirred for 1 hour, during which time a precipitate slowly formed.This was filtered off, washed with water and small amounts of ether, anddried in vacuum over P 0 The crude product was purified by washing withdilute sodium hydroxide, followed by water until the wash water wasneutral, then dried over P 0 under vacuum. There was obtained 460 g.(88.2%) of 4-trifluoromethylbenzophenone O-acetyloxime as a white solid:m.p., 168-171 C.; F NMR (CHCl 6 63.3 p.p.m. (m, J=0.5 Hz.); H NMR (CH Cl6 2.08 p.p.m. (s, 3H), 6 7.6 p.p.m. (m, 9H).

Analysis.Calcd. for C H NO 'F C, 62.54; H, 3.94; N, 4.56; F, 18.76.Found: C, 62.60; H, 3.95; N, 4.73; F, 18.60.

Example 3.4-Trifluoromethylbenzophenone O-Propionyloxime R=H R1=C2H5N-OH l i o- 0 F 01130131001 v NOCCH2CH3 To a solution of g. (0.038 mole)of 4-trifiuoromethylbenzophenone oxime in 45 ml. of ether Was added 3.5g. (0.038 mole) of prop'ionyl chloride. The mixture was allowed to standfor 1 hour at room temperature. The ether was evaporated and the residuewashed with water, dried and recrystallized from n-heptane. The productwas Washed with 5% aqueous NaOH and water, then dried to give 6.3 g.(52%) of 4-trifluoromethylbenzophenone O-propionyloxime as an off-whitesolid: m.p., 118123 C.; H NMR DMSO-d 6 1.03 p.p.m. (t, 3H), 6 2.42p.p.m. (quartet, J=7.9 Hz., 2H), 6 7.77 p.p.m. (m, 9H); F NMR (DMSO-d 661.0 p.p.m. (s).

Analysis.-Calcd. for C H NO F C, 63.55; H, 4.39; N, 4.36; F, 17.74(M.W., 321.30). Found: C, 63.66; H, 4.33; N, 4.59; F, 17.80.

Example 4.4-Trifiuoromethylbenzophenone O-Heptanoyloxime Heptanoylchloride (5.6 g., 0.038 mole) was added dropwise to a solution of 10.0g. (0.038 mole) of 4-trifluoromethylbenzophenone oxime in 30 ml. ofether. The solution was stirred overnight at room temperature. The etherwas evaporated and water added. The product, which solidified slowlywhen chilled, was filtered off, washed with water and dried to yield12.4 g. (87%) of 4-trifluoromethylbenzophenone O-heptanoyloxime as anoff-white solid: m.p., -84 C.; F NMR DMSO-d 6 61.1 p.p.m. (m, J=ca. 0.5Hz.); H NMR (DMSO- d 6 7.45 p.p.m. (m, 9H), 6 2.28 p.p.m. (m, 2H), 61.25 p.p.m. (m, 8H), 6 0.85 p.p.m. (m, 3H); IR (KBr) 5.65;

Analysis.Calcd. for C H NO F C, 66.83; H, 5.88; N, 3.71; F, 15.10 (M.W.,377.41). Found: C, 66.20; H, 5.65; N, 3.58; F, 15.14.

Example 5.4-Triflu0romethylbenzophenone O-Benzoyloxime R C5115 N-OI-I IIit CF3 C 0011 001 ll NO C CaHa am- 4m To a solution of 10 g. (0.038mole) of 4-trifiuoromethylbenzophenone oxime in 25 ml. of diethyl etherwas added dropwise 5.4 g. (0.038 mole) of benzoyl chloride. The solutionwas stirred overnight at room temperature. The ether was evaporated andthe product washed with 5% aqueous sodium hydroxide and water and driedto yield 12.2 g. (87%) of 4-trifiuoromethylbenzophenone O- benzoyloximeas a white solid: m.p., 114-120 C.; F NMR (CDCl 6 63.2 p.p.m. (s, 87%),6 63.3 p.p.m. (m, 13%); IR (KBr) 5.70 4 C=O).

Analysis.Calcd. for C21H14NO2F3: C, H, N 3.79; F, 15.43 (M.W., 369.34).Found: C, 67.87; H, 3.48; N, 3.83; F, 15.47.

Example 6.4Trifiuoromethylbenzophenone O- (N-Methylcarb amoyl Oxime O 8NO NHCH:

A solution of 10 g. (0.038 mole) of 4-trifiuoromethylbenzophenone oxime,1.6 g. (0.028 mole) of methyl isocyanate and 30 ml. of diethyl ether wasallowe to stand at room temperature for 48 hours under a stream ofnitrogen, during which time a solid slowly formed. The ether waspartially evaporated and CCl F was added to precipitate the product,which was filtered 01f and dried to give 5.0 g. (55% based on methylisocyanate) of 4-trifluoromethylbenzophenone O-(N-methylcarbamoyl)oximeas a white solid: m.p., 191193 C.; H NMR 6 7.7 p.p.m. (m, 9H), 6 7.1p.p.m. (broad signal, 1H), 6 2.88 p.p.m. (d, J=4.8 Hz., 3H), 6 2.75p.p.m. (minor impurity); F NMR [(CD CO] 6 63.7 p.p.m. (s).

Analysis.Calcd. for C H N O F C, 59.63; H, 4.07; N, 8.69; F, 17.68(M.W., 322.29). Found: C, 58.98; H, 4.09; N, 8.51; F, 17.94.

Example 7.4-Trifiuoromethylbenzophenone O- (N-Phenylcarbamoyl Oxime INOC INHCsHs A solution of 4.5 g. (0.038 mole) of phenyl isocyanate, g.(0.038 mole) of 4-trifluoromethylbenzophenone oxime and 25 ml. of etherwas stirred overnight at room temperature. After about 30 minutes thereaction mixture became a slurry of white solid and liquid. The productwas filtered 01f, washed with a small amount of ether and water. Asecond fraction was obtained by filtering the filtrate. Both fractionswere dried in vacuum. They were further purified by washing with 5%aqueous NaOH, water, and drying.

Fraction 1: 10 g. of 4 trifiuoromethylbenzophenoneO-(N-phenylcarbamoyl)oxime, oflF-white solid, m.p., 131- 143 C.; H NMR(DMSO-d 6 9.80 p.p.m. and 6 9.74 p.p.m. (singlets, combined area 1H), 67.54 p.p.m. (rn, 14H); F NMR (DMSO-d 6 --61.1 p.p.m. and 6 61.0 p.p.m.(multiplets, 40:60 ratio).

Analysis.-Calcd. for C H N O F C, 65.62; H, 3.93; N, 7.29; F, 14.83(M.W., 384.36). Found: C, 65.51; H, 3.91; N, 7.14; F, 14.92.

Fraction 2: 3.6 g. of 4-trifluoromethylbenzophenone O-(N-phenylcarbamoyl)oxime, off-white solid, m.p., 134- 144 C.; H NMR(DMSO-d,) 6 9.83 p.p.m. and 9.73 p.p.m. ,(singlets, combined area 1H), 67.58 p.p.m. (m, 14H) F NMR (DMSO-d[) 6 -60.9 p.p.m. and 6 60.8 p.p.m.(multiplets, ratio 15:85).

Analysis.--Calcd. for C21H15N202F3Z C, H, N, 7.29; F, 14.83 (M.W.,384.36). Found: C, 65.03; H, 3.92; N, 6.80; F, 14.85.

Example 8.2-Trifiuoromethylbenzophenone O- Acetyloxime 0 NO JCI-Is QSJLH...

To a solution of 2.0 g. (0.0076 mole) of 2-trifluoromethylbenzophenoneoxime in 10 ml. of ether was added dropwise an excess of acetyl chlorideat room temperature. The ether was evaporated, the residue washed withwater and dried. The crude product was recrystallized from n-hexaneusing dicolorizing carbon, to give 1.24 g. (53.2%) of 2trifluoromethylbenzophenone O-acetyloxime as a white crystalline solid:m.p., 74.5-79.5" 0; P NMR 6 61.2 p.p.m. (m); H NMR (CDC1 6 7.4 p.p.m.(m, 9H), 6 1.98 p.p.m. (s, 3H).

Analysis.-Calcd. for C H NO F C, 62.54; H, 3.94; N, 4.56; F, 18.55(M.W., 307.28). Found: C, 62.58; H, 3.96; N, 4.60; F, 18.83.

6 Example 9.--4-Methoxy-4'-Trifiuoromethylbenzophenone O-AcetyloximeR=OCH3 R =CHs llvofl (I? OH 1 crr.o l- Q CF3 2 To don. CH.O @L@ CF. H0.To a solution of 10 g. (0.035 mole) of4-methoxy-4-trifiuoromethylbenzophenone oxime in 50 m1. of diethyl etherwas added dropwise 2.7 g. (9.034 mole) of acetyl chloride at 22 to 282C. A solid slowly formed. The mixture was stirred for 1 hour and cooled.The solid was filtered off, washed with ether and water and vacuumdriedover P 0 There was obtained 9.4 g. (82.5%) of 4-methoxy 4trifiuoromethylbenzophenone O-acetyloxime as a white solid: m.p., 127140C.; H NMR 6 7.65 p.p.m. (m, 8H), 6 3.89 p.p.m. (s, 3H), 6 2.04 p.p.m.(s, 3H); F NMR [(CD CO] 6 62.2 p.p.m. (m, 6 62.0 p.p.m. (s, 5%).

Analysis.Calcd. for C H NO F C, 60.54; H, 4.18; N, 4.15; F, 16.90 (M.W.,337.20). Found: C, 59.89, 59.66; H, 4.02, 4.15; N, 3.97, 4.01; F, 17.15.

Example 10.4-Trifluoromethylbenzophenone O- Chloroacetyloxime R=H R=CCla NOH II 4 CF:- -C CICHaCCl u N-O 0 011401 3.24; N, 4.10. Found: C,55.93, 55.72; H, 2.79, 2.94; N, 4.07, 3.79.

Example 1 1.-4-Trifiuoromethylbenzophenone O-Trichloroacetyloxime To asolution of 5.3 g. (0.02 mole) of 4-trifluoromethylbenzophenone oxime in50 ml. of ether was added 3.7

g. (0.02 mole) of trichloroacetyl chloride. The solution was evaporatedto dryness, yielding 6.5 g. of 4-trifluoromethylbenzophenoneO-trichloroacetyloxime, mp. 92- 102 C., H NMR (CDCl /TMS), 6 7.5 ppm.(m).

Analysi .Calcd. for C H F Cl NO C, 46.80; H, 2.21; N, 3.41. Found: C,46.46; H, 2.26; N, 3.17, 3.19.

Example A This example illustrates the crop yield increasing effect of4-trifiuoromethylbenzophenone O-acetyloxime on soybeans when applied tothe foliage.

Soybeans were grown in a mixture of equal parts of vermiculite, peat andgravel in four pots in a controlled environment growth room, each potcontaining two plants. The environment was a 12-hour photoperiod with4300 ft.-c., temperature 75 F. day and 64 F. night, and a continuousrelative humidity of 75%. A suspension of 4-trifluoromethylbenzophenoneO-acetyloxirne was applied as a foliar spray to run-off and as a soildrench treatment at the early flowering stage of development. Theelapsed time from treatment to harvesting was 55 days. The treatmentcaused an increase in the number of pods and an increase in the numberand weight of seeds per plant when compared to the untreated control.The following results were obtained:

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A compound of the formula N0. of-

Dry wt. Rate, Pods/ Seeds] seeds/ Treatment 1b./aere pot pot, pot (g.)

Mo 90. 5 156. 7 29. 65 i-tritluoromethyl-benzophenone O-aeetyloxime. 94.2 165.3 33. 97 M 94. 0 146. 7 35. Untreated control 81. 0 138.0 27.80

Example B Bushels/ Percent acre of control Plots:

Control 46. 1 100 Treated 52. 9 117 7. The compound of claim 1 in whichR=H and R =CH 2-trifiuoromethylbenzophenone O-acetyloxime. 8. Thecompound of claim 1 in which R=OCH and R =CH4-methoxy-4'-trifluoromethylbenzophenone O- acetyloxime.

References Cited UNITED STATES PATENTS 3,169,989 2/1965 Tieman et al.260566 AB 3,503,732 3/1970 Cahoy 260566 AE 3,733,359 5/1973 Hubele260566 AE OTHER REFERENCES Chemical Abstracts, vol. 56, column 12,895(1962).

LEON ZITVER, Primary Examiner G. A. SCHWARTZ, Assistant Examiner US. Cl.X.R.

71-l21; 260566 AE

1. A COMPOUND OF THE FORMULA